* has an niaid ordinal scale score \<5; * is on high-flow oxygen or any form of noninvasive ventilation, excluding continuous positive airway pressure (cpap) alone for sleep disorders (e.g., obstructive sleep apnea); * has significant cardiovascular disease, defined by myocardial infarction, arterial thromboembolism, or cerebrovascular thromboembolism within 3 months prior to randomization; symptomatic dysrhythmias or unstable dysrhythmias requiring medical therapy; angina requiring therapy; symptomatic peripheral vascular disease; new york heart association class 3 or 4 congestive heart failure; grade 3 hypertension (diastolic blood pressure greater than or equal to 100 mmhg or systolic blood pressure greater than or equal to 160 mmhg); history of congenital prolonged qt syndrome, or known dyslipidemia; * is currently taking any investigational products, other than the study drug; * has any other condition that, in the opinion of the investigator, could interfere with (or for which the treatment might interfere with) the conduct of the clinical trial or interpretation of the clinical trial results or that would place the subject at undue risk by participating in the clinical trial.

* has an niaid ordinal scale score \<5; * is on high-flow oxygen or any form of noninvasive ventilation, excluding continuous positive airway pressure (cpap) alone for sleep disorders (e.g., obstructive sleep apnea); * has significant cardiovascular disease, defined by myocardial infarction, arterial thromboembolism, or cerebrovascular thromboembolism within 3 months prior to randomization; symptomatic dysrhythmias or unstable dysrhythmias requiring medical therapy; angina requiring therapy; symptomatic peripheral vascular disease; new york heart association class 3 or 4 congestive heart failure; grade 3 hypertension (diastolic blood pressure greater than or equal to 100 mmhg or systolic blood pressure greater than or equal to 160 mmhg); history of congenital prolonged qt syndrome, or known dyslipidemia; * is currently taking any investigational products, other than the study drug; * has any other condition that, in the opinion of the investigator, could interfere with (or for which the treatment might interfere with) the conduct of the clinical trial or interpretation of the clinical trial results or that would place the subject at undue risk by participating in the clinical trial.

- has an niaid ordinal scale score <5; - is on high-flow oxygen or any form of noninvasive ventilation, excluding continuous positive airway pressure (cpap) alone for sleep disorders (e.g., obstructive sleep apnea); - has significant cardiovascular disease, defined by myocardial infarction, arterial thromboembolism, or cerebrovascular thromboembolism within 3 months prior to randomization; symptomatic dysrhythmias or unstable dysrhythmias requiring medical therapy; angina requiring therapy; symptomatic peripheral vascular disease; new york heart association class 3 or 4 congestive heart failure; grade 3 hypertension (diastolic blood pressure greater than or equal to 100 mmhg or systolic blood pressure greater than or equal to 160 mmhg); history of congenital prolonged qt syndrome, or known dyslipidemia; - is currently taking any investigational products, other than the study drug; - has any other condition that, in the opinion of the investigator, could interfere with (or for which the treatment might interfere with) the conduct of the clinical trial or interpretation of the clinical trial results or that would place the subject at undue risk by participating in the clinical trial.

- has an niaid ordinal scale score <5; - is on high-flow oxygen or any form of noninvasive ventilation, excluding continuous positive airway pressure (cpap) alone for sleep disorders (e.g., obstructive sleep apnea); - has significant cardiovascular disease, defined by myocardial infarction, arterial thromboembolism, or cerebrovascular thromboembolism within 3 months prior to randomization; symptomatic dysrhythmias or unstable dysrhythmias requiring medical therapy; angina requiring therapy; symptomatic peripheral vascular disease; new york heart association class 3 or 4 congestive heart failure; grade 3 hypertension (diastolic blood pressure greater than or equal to 100 mmhg or systolic blood pressure greater than or equal to 160 mmhg); history of congenital prolonged qt syndrome, or known dyslipidemia; - is currently taking any investigational products, other than the study drug; - has any other condition that, in the opinion of the investigator, could interfere with (or for which the treatment might interfere with) the conduct of the clinical trial or interpretation of the clinical trial results or that would place the subject at undue risk by participating in the clinical trial.